The Mystery of Danielle Fenton
by melanshi
Summary: One night, an injured young girl shows up at Mr. Lancer's front door. He lets her come in and takes care of her until her father comes. Not bad, right? Wrong. Lancer suddenly finds himself the target of a powerful ghost and has to escape to the Ghost Zone with the girl and Danny Fenton. What secrets are the two hiding? And who is this ghost? Danny/Danielle Father/Daughter
1. Chapter 1

**I don't own Danny Phantom.**

It was around ten o'clock at night and lightning flashed outside the house of Mr. Lancer. The teacher glanced up briefly before grabbing the next paper.

Danny Fenton.

Lancer sighed as thunder boomed again. Danny had shown so much potential at the beginning of his freshman year. And then there was some accident in his parent's lab. Suddenly after that, his grades started dropping and he started skipping class. Mr. Lancer could always expect to see the teen in detention after school.

The teacher didn't even begin grading Danny's paper when there was a knock on his front door. He sighed and went to open it.

A young girl stood there. Her face was bruised and her clothes were soaked and covered with mud. Her right sleeve was torn and she seemed exhausted.

"_Hunt For Red October!_" Mr. Lancer yelled in shock.

The girl weakly looked up at him with tired icy blue eyes. "Help… me…"

She collapsed.

Lancer stared at her for a second in mute shock, observing her. Her raven hair was tied back in a ponytail with a red beanie in her hair. She wore a dirty blue sweatshirt, equally dirty red shorts, and blue sneakers. She reminded him of Danny Fenton. Maybe it was because the teacher was thinking of the student.

He picked her up carefully, surprised at how light she was, and carried her to the couch. He gently rested her there and went to find his first aid kit.

He returned to find that she was already awake and looking at the cut on her arm. A smile lit up her face.

"Daddy was right," she whispered. "Super healing is a blessing!"

Mr. Lancer was confused by this but walked over to her. She jumped and inched away from him, blue eyes wide.

"Whoa, calm down," he said.

The girl looked at him as she inched away some more.

"I'm a teacher," Mr. Lancer continued. "It's my job to help students."

The girl found her voice again. "You don't happen to work for Vlad Masters, do you?" she asked, glaring at him with narrowed eyes.

Mr. Lancer shrugged. "Not directly. He's the mayor though."

"Aw, flames!" The girl spat out. "He's the _mayor_?"

Mr. Lancer nodded.

She whispered some very un-ladylike curses that the teacher was surprised she actually knew under her breath.

"So… what's your name?" Mr. Lancer asked.

The girl blinked. "Danielle. Everyone calls me Dani though."

"How old are you?"

"Thirteen."

"Do you have any family you could call?"

Dani thought for a second. She hesitated before nodding. "Um, Danny Fenton…"

"He's one of my students." No wonder Danielle looked like Danny. They were related.

Danielle's eyes lit up. "Do you have a phone?"

Mr. Lancer nodded and handed her it.

She dialed the number.

The person on the other side said something.

"Can I please speak to Danny? Tell him it's Danielle."

Mr. Lancer got up. "Would you like something to eat?"

Danielle nodded. "Do you have any fudge?"

The teacher grinned and nodded. This girl obviously was a Fenton. He walked into the kitchen. He couldn't help overhear the conversation she was having.

"Hello, Daddy! It's Dani!" Danielle said. She giggled. "I'm fine, Dad! I just had a run in with Skulker." She paused. "I can practically feel the scary eyes you're giving him now. He was working for Plasmius." Another pause. "Wow. I didn't even know you knew half of those words! Anyway, I managed to drag myself to the nearest house. Turns out the owner is one of your teachers." She paused again. "Sure. Um, he's wearing a blue short sleeved shirt with a black tie, gray pants, and black shoes. He's bald too." A fourth pause. "Thanks, Dad! See you soon!"

Lancer walked back in and handed the girl her fudge. Her eyes lit up as she shoveled the candy in. The teacher laughed. The girl obviously was related to Jack Fenton.

"What's your name?" She asked, mouth full of fudge.

He smiled kindly. "You can call me Mr. Lancer."

Her eyes widened. "Mr. Lancer?" she asked. "The Mr. Lancer?"

He blinked.

"Daddy's told me about you! You were involved in the whole Dan incident!" Dani exclaimed.

Mr. Lancer blinked again. "Your dad? And who's Dan?"

"You don't remember?" Danielle exclaimed. "Dan is—"

"Not to be talked about for the sake of my sanity." Both people turned to the doorway to see Danny Fenton leaning there, arms crossed.

Dani grinned. "Daddy!" She ran up and hugged him.

"Did she just call you 'Daddy', Mr. Fenton?" Mr. Lancer asked, shocked.

Danny sighed before nodding. "I'm her adopted father."

Danielle's eyes watered. "Daddy, Plasmius is after me again."

Danny knelt down. "I know, little halfa. Daddy's here, though. I'll protect you. I promised that nothing would ever happen to you, remember?"

She nodded, ponytail bouncing.

Danny sighed and ran a hand through his messy black hair. "I'm taking you to the lair."

_The lair? _Mr. Lancer thought.

"Lair?" Dani thought out loud. "Since when do you have a lair?"

Danny smiled. "Correction. Since when do _we _have a lair?" He chuckled. "You missed the Christmas Truce. The lair was Clockwork's present to us."

_Christmas Truce? And who's Clockwork? _Mr. Lancer thought.

Danny looked up at Mr. Lancer. "Thanks for taking care of my daughter, Mr. Lancer," he said in a voice filled with authority that the teacher normally didn't associated with little shy Danny Fenton. "I'll be taking her home now."

He nodded to Mr. Lancer quickly before taking his daughter's hand and leading her out the door. The teacher could've sworn he saw a blinding flash as they left.

…

Danny and Danielle phased into the older halfa's room and transformed from Danny Phantom and his daughter Dani Phantom to Daniel Fenton and his daughter Danielle Fenton.

Danny led the young girl towards his closet and opened it. Danielle curiously looked past him to see a purple door behind the clothes. Her father opened it and ushered her in.

Danielle looked around. They were in an entranceway with an ice statue of Danny with Danielle on his shoulders. They were another purple door labeled "Ghost Zone". She spotted two more doors: one labeled "Tucker's Place" and another labeled "Sam's Mansion".

Danny led her through an opening into a kitchen that looked like the Fenton's kitchen. He walked through the kitchen into a living room.

The room had a black carpet on a hardwood floor and a black ceiling. The walls were white. There was a black and white sofa and two chairs in the middle of the room. Across from that was a flat screen TV with video games and movies all around it.

"Sorry for the mess," Danny said, rubbing the back of his neck. "Tucker and I had a Guys Movie Night last night since Sam was out at dinner with her parents. C'mon! Over here is your bedroom!"

Dani looked where he was pointing and saw a blue door with rocket stickers and "Dani's Room" written on it. She opened the door and stepped inside.

There was a queen-sized bed across from a flat screen TV. Otherwise the room was bare.

Dani looked up and gasped. On the ceiling there was a screen showing outer space.

"You can change it," Danny said, handing her the remote. He checked his watch before kissing her on the forehead. "I've gotta go, little halfa. Goodnight!"


	2. Chapter 2

**Still don't own DP.**

_ Phantom floated down to the female ghost girl and reached out to free her, but was electrocuted himself. He cried out and stepped back before shooting a ghost ray at the restraints holding the girl down. _

_ The Wisconsin Ghost gripped the wall as he got up. "It's going to take more than your little plasma rays to break those ties, Daniel."_

_ The Red Huntress flew up to the ghost and blasted him through the wall. _

_ The ghost girl screamed again. Phantom ignored the older ghost's words and kept trying to break her restraints. It didn't work. Her feet were turning to green ectoplasm._

_ "I can't break them, Danielle. There's only one thing left to try," he said, pulling a vial of green liquid out from behind him. "Feeling brave?"_

_ "A little weak in the knees actually," Danielle said. She looked down at her melting form. "And I don't even have knees anymore!"_

_ "Well then, let's hope my dad didn't mend this Achilles heel!" Phantom said. He squirted Danielle in the arm._

_ "I think it's too late. Bye Danny. Thanks for…" the girl said weakly as she melted._

_ "Oh no," Phantom said._

_ Danielle fully melted into ectoplasm at the base of the examination table. _

_ "No!" Phantom yelled. "No! Dani, I failed you…" he put his head in his hands. "I'm so sorry."_

_ The ectoplasm bubbled behind him._

…..

Beep! Beep! Beep!

Mr. Lancer groaned and hit the Off button on his alarm clock. He sat up slightly and thought about his dream. He felt like it wasn't finished yet. And Phantom's voice sounded strangely familiar along with that Danielle girl's voice.

"Were you having a nightmare?"

Lancer shrieked and jumped up before he noticed that it was just Dani.

"Dani?" Mr. Lancer asked. "Why are you here?"

She shrugged and blew a strand of raven hair out of her eyes. "Daddy was busy and I was bored of hanging out at the lair."

Mr. Lancer scowled. "Busy? Probably playing video games and slacking off on his homework."

Dani blinked. "Dad doesn't slack off on homework." She bit her lip. "He has some… important things to do."

"Like take care of you?"

"That's a part of it. But some other things. Trust me. Dad may seem troubled on the outside, but once you get to know him—" Here she smirked at some memory. "—Everything he does is for a reason."

She sat down on Lancer's bed, lost in thought.

"Hey, Dani?" Lancer asked after a few minutes.

"Huh? What?" she asked.

"Last night you mentioned a guy named Plasmius and said that he was after you again. What was that all about?"

She sighed and brushed some hair out of her face and stayed quiet for a long time before breaking down in tears.

Lancer was shocked about her sudden breakdown and went over to hug her.

"I-I-I can't take it anymore!" Dani wept. "Why can't I be a normal little girl? Nooooo… instead I'm just some freak of nature who doesn't belong in the Ghost Zone or the human world and endangers everyone she comes in contact with!"

Lancer hugged her. "Is this Plasmius guy putting you in danger? We can go to the police about it."

She shook her head and wiped away a tear. "You can't tell the police about Plasmius. It'll do no good since Plasmius is—"

"Right here."

Lancer looked up to see a very familiar ghost.

The Wisconsin Ghost.

….

Danny flew around town, scanning the streets in a panic. He had gotten back from patrol to find Danielle gone from the lair.

"Danielle!" He called. "Danielle Phantom!"

There was no response. The boy flew down to the park and rested his head in his hands. Where was Dani? Did Vlad have her?

Vlad.

The ghost boy's eyes glowed a dangerous green and his incisors sharpened into fangs. Vlad must have her.

He took off so fast, he nearly broke the sound barrier.

…

Neither Danielle nor Lancer moved as Vlad circled them, observing.

"Still stable," Vlad muttered to himself, observing the halfa girl. "Most likely due to that invention Daniel gave her."

"Leave Daddy alone," Danielle cried out bravely.

Plasmius chuckled. "'Daddy'? Oh please, girl. A father is a person who helped bring you into this world." He smirked. "I helped do that, therefore by definition, I am your father."

Lancer froze. This ghost was Dani's technical father?

"Actually, a father is a person who shares the same DNA as his child, _Vlad_. Danielle and I have the same DNA."

Everyone turned to see that it was Danny Fenton who was standing in the doorway, upper lip curled up in a snarl, showing a pointy fang.

Mr. Lancer didn't pay attention to the fang. What he was thinking about was how Danny had said yesterday that Dani was his adopted daughter yet today he had revealed that he shared the same DNA as her.

"Daniel," Vlad spat out the younger halfa's name like poison. "Nice of you to join us."

Danny walked forward a bit more, eyes glowing a fierce electric green. "Leave them alone, Plasmius. They don't need you after them."

"Au contraire, Daniel. William here helped Danielle after my pawn attacked her. Danielle here betray me and attacked me," Vlad said.

Danny smiled a bit. "And a twelve year old girl beat you, Plasmius. Twice."

The older halfa growled and picked up Dani by her wrist. He shocked her.

Danny smile faded away as she screamed before fainting. The ghost threw her at Lancer, who caught her.

"She's weak and so are you, Daniel," Vlad said. He held out a gloved hand. "Join me."

Danny looked at Vlad's hand and then towards Vlad.

He took his hand.

And bit it.

Vlad cried out as he stumbled backwards. Danny still had his fangs that tore his glove and left puncture marks in his skin.

"Why you little brat!" Vlad shrieked.

He turned towards Lancer and held up a hand that glowed magenta.

The last thing that the teacher saw before he was knocked unconscious was a ball of magenta ecto-energy flying at him.

**Oh no! Is Dani okay? Will Lancer be okay? Why does Danny have fangs?**


End file.
